Zhang Yun 張允

In Chapter 40 of the Romance, when Liu Biao dies, Lady Cai consults Cai Mao and Zhang Yun, forges a will making the second son Liu Cong lord of Jing Province, and only then mourns and announces the death. Romance, Ch. 40 §16

In Chapter 41, when Liu Bei leads the people to the east gate of Xiangyang and calls on Liu Cong to open the gate, Liu Cong is too afraid to come out, and Cai Mao and Zhang Yun go straight up onto the watchtower and order the soldiers to shoot down a hail of arrows. Then Wei Yan, inside the city, rebukes them, crying, 'Cai Mao, Zhang Yun, you traitors who have sold out the state!', cuts down the officers and men guarding the gate, and opens the city gate. Romance, Ch. 41 §10–11

When Cao Cao sends a man from Fancheng to summon Liu Cong, Liu Cong is too afraid to go, and Cai Mao and Zhang Yun ask to go in his place. The two meet Cao Cao at Fancheng, and when Cai Mao reports that the troops of Jing Province number 280,000 in all and that the more than 7,000 warships, large and small, were originally under the charge of the two of them, Cao Cao makes Cai Mao Marquis Who Guards the South and Grand Commander of the Navy, and Zhang Yun Marquis Who Aids Compliance and Vice Commander of the Navy. When Xun You asks why he gives such high ranks to a band of flatterers, Cao Cao answers that because the northern troops are not used to fighting on water he is using the two men for the time being, and will deal with them separately once the matter is accomplished. Romance, Ch. 41 §20 · 22–24

The two return and report to Liu Cong that Cao Cao has promised to memorialize the Son of Heaven so that Liu Cong may govern Jing and Xiang forever, and the next day Liu Cong, together with his mother Lady Cai, goes to receive Cao Cao bearing the seal and ribbon and the military tallies. Cai Mao and Zhang Yun have the people of Xiangyang burn incense and bow to welcome Cao Cao. Romance, Ch. 41 §25

In Chapter 45 Cao Cao makes Cai Mao, Zhang Yun and the other generals who had surrendered from Jing Province his vanguard and reaches Sanjiangkou, but is defeated by the ships of Gan Ning and others. When Cao Cao rebukes the two, saying that they were defeated although Eastern Wu had few troops because they did not put their minds to it, Cai Mao proposes first building a water camp and training every day. When Cao Cao tells them that, since they are already commanders of the navy, they should handle it as they see fit, Zhang Yun and Cai Mao set up twenty-four water gates along the river, place the large ships outside as a city wall and the small ships inside, and train the navy. Zhou Yu, secretly spying on this water camp, is astonished that they have deeply mastered the secrets of naval warfare, and thinks that because the two have long lived in Jiangdong and are skilled in fighting on water, he can defeat Cao Cao only after first getting rid of them. Romance, Ch. 45 §27–28 · 30–31 · 33

Jiang Gan, sleeping in Zhou Yu's tent, steals a look at a letter inscribed 'Respectfully sealed by Cai Mao and Zhang Yun', which says that they surrendered to Cao Cao only because circumstances forced them and that they will present Cao Cao's head at the first opportunity. Jiang Gan also overhears someone outside saying, 'The two commanders Zhang and Cai say that they cannot act in haste,' and returns to tell Cao Cao. When Cao Cao summons the two and orders them to advance, Cai Mao replies that the troops are not yet well trained, and Cao Cao in a rage has the two dragged out and beheaded. When the heads are presented, Cao Cao realizes that he has fallen for a ruse, but tells his generals that he beheaded the two because they had been negligent of military law. Romance, Ch. 45 §47–48 · 50–54 · 56

In Chapter 47, when Jiang Gan comes again, Zhou Yu changes countenance and rebukes him, saying that last time he stole a private letter and reported it to Cao Cao, so that Cai Mao and Zhang Yun were killed and Zhou Yu's own plan could not be accomplished. Romance, Ch. 47 §24